barrier repair

DESCRIPTION

What It Does: Softens and conditions skin by integrating into sc lipid bilayers, delivers essential fatty acids (oleic, linoleic, linolenic) for barrier lipid synthesis, and provides rich, non-stripping moisturisation.

Why It's Used: Natural carrier oils provide the closest compositional match to endogenous sc lipids, delivering emolliency through genuine barrier integration rather than simple surface occlusion.

How It Works: Fatty acid triglycerides partition into sc lipid bilayers — oleic acid (c18:1) provides fluid, emollient integration; linoleic acid (c18:2) acts as essential ceramide precursor; saturated fatty acids provide more occlusive barrier reinforcement.

Typically Found In: Moisturisers,facial oils,natural skin care

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–100%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Essential fatty acids — linoleic (c18:2, n-6) and α-linolenic (c18:3, n-3) acids — cannot be synthesised by the body; topical delivery through carrier oils provides direct substrate for ceramide and eicosanoid biosynthesis in the epidermis.

Last Verified: Cosing database,avena sativa (oat) kernel oil carrier oil botanical review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Reduces skin inflammation, soothes irritation, promotes wound healing, and enhances penetration of co-formulated actives.

Why It's Used: Premium natural soothing active with combined anti-inflammatory, wound healing, and penetration-enhancing activity – clinically validated across sensitive, reactive, and irritated skin types.

How It Works: Inhibits nf-kb pathway reducing pro-inflammatory cytokines il-1β, il-6, tnf-α. enhances stratum corneum lipid fluidity increasing penetration of co-delivered actives. antimicrobial against s. aureus and c. albicans. promotes keratinocyte migration for wound healing.

Typically Found In: Sensitive skin products,post-procedure formulations,anti-irritant formulas,wound healing

TECHNICAL DETAILS

Primary Category: Active ingredient – soothing / anti-inflammatory

Secondary Functions: Anti-inflammatory,penetration enhancement,antimicrobial

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–1%

SOURCING & ETHICS

Vegan Status: Yes – from candeia tree (vanillosmopsis erythropappa) or synthetic

Halal Status: Yes

Source Notes: Natural (-)-alpha-bisabolol from brazilian candeia tree is more sustainable and potent than chamomile-derived bisabolol. synthetic (±)-bisabolol is racemic with slightly lower anti-inflammatory potency.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; ideal for reactive and sensitive skin.

Safe for Sensitive Skin: Yes – particularly recommended for sensitive skin

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Ceramides,panthenol,allantoin,hyaluronic acid,centella asiatica

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Bisabolol's dual function as both an anti-inflammatory and a penetration enhancer is synergistic – by reducing the inflammatory response that increases barrier tightness while simultaneously fluidizing stratum corneum lipids, it provides enhanced delivery of co-formulated actives in the very conditions where delivery is most needed.

Last Verified: Cosing database,piazza et al. bisabolol anti-inflammatory study,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides antioxidant protection from reactive oxygen species, reduces inflammatory cytokine production in skin, and conditions skin surface through the plant's secondary metabolite complex.

Why It's Used: Chosen for its natural origin narrative, traditional use heritage, and multi-functional phytochemical profile that supports several concurrent skin care claims from one ingredient.

How It Works: Polyphenols, terpenoids, and alkaloids in the extract scavenge ros via hydrogen atom transfer, inhibit nf-kb or cox-2 inflammatory pathways, and interact with skin surface proteins for conditioning.

Typically Found In: Botanical skin care,natural products

TECHNICAL DETAILS

Primary Category: Active ingredient – antioxidant

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Plant secondary metabolites evolved as uv photoprotectants and antimicrobial agents — mechanisms that directly translate to cosmetic antioxidant and anti-inflammatory activity in human skin.

Last Verified: Cosing database,boerhavia diffusa root extract botanical review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides humectant hydration and active ingredient solubilization with excellent skin feel.

Why It's Used: Preferred glycol humectant in premium and k-beauty formulations for superior skin feel vs propylene glycol with equivalent functionality.

How It Works: Two hydroxyl groups at 1,3-positions provide water binding and solvent activity. better tolerated than propylene glycol with minimal sensitization risk. 4-carbon backbone provides slightly greater hydrophobic character enabling dissolution of less polar actives vs pg.

Typically Found In: Toners,essences,serums,k-beauty formulas

TECHNICAL DETAILS

Primary Category: Functional ingredient – glycol humectant

Secondary Functions: Tewl reduction,skin plumping

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–10%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Synthetic or naturally derived. excellent aqueous solubility.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Ceramides,emollients,occlusives,glycerin,hyaluronic acid

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

K-beauty's preference for butylene glycol over propylene glycol is driven by two factors: bg's superior skin feel (less tacky than pg's higher viscosity) and its lower sensitization potential (1,3-bg has better spatial distribution of hydroxyl groups that reduces protein interaction vs pg's 1,2-position oh groups).

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides a dry, weightless application vehicle that evaporates cleanly leaving actives and non-volatile silicones deposited on skin — eliminating the residual heaviness of conventional liquid carrier solvents.

Why It's Used: Cyclosiloxanes are the unique volatile silicone solvents that dissolve non-volatile silicones (dimethicone, cyclomethicone), organic uv filters, and lipophilic actives, providing the sensory-superior dry-touch application experience in premium formulations.

How It Works: Cyclosiloxane vapour pressure (d5 cyclopentasiloxane ~0.3 mmhg at 25°c) provides clean evaporation at body temperature. the cyclic ring structure provides lower boiling point than equivalent linear dimethicone, enabling faster evaporation while the ring conformation maintains the silicone's low surface energy for smooth application.

Typically Found In: Primers,antiperspirants,sunscreens

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–50%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Cyclopentasiloxane (d5) and cyclohexasiloxane (d6) are under eu regulatory review for potential environmental persistence (pbt assessment) — formulators should monitor eu regulation 2018/35 implementation for restrictions in wash-off products.

Last Verified: Cosing database,eu cyclosiloxane regulatory review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides silicone-characteristic silky feel and skin protection with adjustable viscosity.

Why It's Used: The benchmark cosmetic silicone – sets the gold standard for silky application feel, spreadability, and skin protection in virtually all skin care categories.

How It Works: Polydimethylsiloxane chain flexibility provides extremely low surface tension and high spreadability. inert si-o backbone provides chemical stability and excellent skin tolerance. occlusive film formation reduces tewl. higher viscosity grades provide more intense conditioning.

Typically Found In: Moisturizers,foundations,primers,sunscreens – nearly universal

TECHNICAL DETAILS

Primary Category: Functional ingredient – polydimethylsiloxane

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–30%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Dimethicone's exceptional silky feel arises from its very low intermolecular attractive forces (weak van der waals forces due to non-polar methyl groups) that allow silicone chains to slide freely over skin. the coefficient of kinetic friction for pdms against skin (~0.04) is among the lowest of any cosmetic material – explaining why even small amounts transform product feel.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides specialty silicone performance — elastomeric skin feel, water-soluble silicone activity, or enhanced hair cuticle conditioning — depending on the specific functional modification.

Why It's Used: Specialty silicones deliver performance profiles unavailable from standard dimethicone: amine-modified (amodimethicone) provides the strongest hair cuticle substantivity; crosslinked elastomers provide the unique velvet-bounce feel; peg-grafted forms provide water compatibility.

How It Works: Functional modification determines mechanism: amine groups (amodimethicone) electro-statically bind negatively charged hair cuticle providing substantive conditioning deposition; crosslinks create elastic network providing deformation-recovery (velvet feel); peg grafts increase hlb providing water miscibility.

Typically Found In: Hair conditioners,primers,specialty formulas

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–20%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Amodimethicone's amine groups have pka ~9 — at typical conditioner ph 4–5, they are fully protonated (–nh₃⁺) providing maximum cationic character for electrostatic attraction to negatively charged damaged hair cuticle.

Last Verified: Cosing database,specialty silicone performance review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Stabilises o/w emulsions by reducing interfacial tension, solubilises oils and fragrances in aqueous systems, and wets oil-phase components for improved formulation homogeneity.

Why It's Used: Peg emulsifiers are selected for their precise hlb, broad ph stability (unlike soap emulsifiers that lose function at acidic ph), and compatibility with both anionic and cationic co-ingredients in the formulation system.

How It Works: Peg chain length determines hlb: longer peg = higher hlb = more hydrophilic = better o/w emulsification. at the o/w interface, the peg chain extends into the water phase forming a hydrated steric barrier that prevents droplet coalescence. nonionic character provides ph-independent function across the full cosmetic ph range.

Typically Found In: Emulsions,fragrance solubilisation

TECHNICAL DETAILS

Primary Category: Active ingredient – cosmetic active

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–10%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Mixed peg emulsifier systems (e.g., peg-100 stearate + glyceryl stearate) form more cohesive interfacial films than single emulsifiers — the geometric complementarity of the co-emulsifier pair providing better mechanical emulsion stability than either component alone.

Last Verified: Cosing database,lauryl peg-9 polydimethylsiloxyethy peg emulsifier review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides stable vitamin e delivery with antioxidant activity after esterase hydrolysis in skin.

Why It's Used: The formulation-stable vitamin e — tocopheryl acetate's ester protection prevents oxidative degradation during shelf life while releasing active tocopherol in skin for equivalent biological activity.

How It Works: Acetate ester blocks the phenolic oh group responsible for oxidation and radical scavenging. skin esterases cleave acetate bond releasing free tocopherol. released tocopherol provides lipid peroxyl radical scavenging in cell membranes. also provides direct emollient and skin conditioning.

Typically Found In: Moisturisers,sunscreens,anti-aging products — extremely widespread

TECHNICAL DETAILS

Primary Category: Active ingredient – stable vitamin e ester

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–5%

SOURCING & ETHICS

Vegan Status: Conditional – natural from vegetable oils (soy, sunflower); synthetic dl-form

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: The d-alpha-tocopheryl acetate (natural isomer) is biologically superior to dl-alpha-tocopheryl acetate (racemic synthetic) for skin antioxidant activity. ingredient label d- vs dl- prefix identifies natural vs synthetic origin.

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Tocopheryl acetate's conversion to active tocopherol in skin is quantitatively efficient: skin esterase activity is sufficient to cleave 60-80% of applied tocopheryl acetate within 24 hours of application. however, the conversion rate varies with skin condition (eczematous or barrier-compromised skin has reduced esterase activity), meaning tocopheryl acetate efficacy may be reduced precisely in the skin conditions that most need antioxidant support.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides antioxidant protection, soothing anti-inflammatory effects, and skin-conditioning benefits through plant-derived polyphenols and phytochemicals.

Why It's Used: Plant extracts concentrate bioactive phytochemicals evolved for environmental protection — uv, microbial, and oxidative stressors — that translate to skin benefits.

How It Works: Polyphenols (flavonoids, phenolic acids) inhibit nf-κb-mediated inflammatory signaling, scavenge reactive oxygen species through electron donation, and chelate pro-oxidant metal ions to reduce oxidative skin damage.

Typically Found In: Serums,toners,moisturizers,masks,essences

TECHNICAL DETAILS

Primary Category: Botanical extracts

Secondary Functions: Antioxidant,anti-inflammatory

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1–10%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Plant-derived extract; no animal components.

SKIN COMPATIBILITY

Irritancy Rating: 1899-12-31 00:00:00 -0800

Sensitivity Concerns: Low sensitization potential at recommended use concentrations.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Well-characterized cosmetic ingredient with established safety profile. generally non-irritating at typical use concentrations. suitable for leave-on and rinse-off cosmetics.

Works Well With: Niacinamide,hyaluronic acid,vitamin c,ceramides

Avoid Combining With: Strong oxidizing agents

SCIENTIFIC NOTE

Plant secondary metabolites (flavonoids, terpenes, phenolic acids) are biosynthesized as defense compounds against uv, herbivores, and pathogens. their anti-inflammatory activity typically derives from competitive inhibition of cox-2 and 5-lox enzymes (ic50 1–50 µm), while antioxidant activity involves single electron transfer (set) and hydrogen atom transfer (hat) mechanisms with structure-dependent rate constants.

Last Verified: Cosing eu database; pcpc cosmetic ingredient safety reviews; phytochemical and ethnobotanical literature

Primary Sources: 2025-01-15